Photoelectric conversion element, photoelectric conversion device, mobile body, and building material

Abstract

The present invention addresses the problem of providing a photoelectric conversion element having an improved short-circuit current density. In order to solve the problem, the present invention provides a photoelectric conversion element having a first electrode (6), a second electrode (2), and a photoelectric conversion layer (4) that is disposed between the first electrode (6) and the second electrode (2) and contains a crystal of a perovskite structure, characterized in that: the photoelectric conversion element includes a charge transport layer (5) provided between the photoelectric conversion layer (4) and the first electrode (6) and containing an amorphous body of a cyclic conjugated compound comprising a plurality of pyrrole rings conjugated to each other; and, with respect to the charge transport layer (5), there is no diffraction peak having a half-value width of 0.5° or less within a range in which the Bragg angle 2θ is 6.5° to 8.5° inclusive in an X-ray diffraction spectrum using CuKα rays.

Description

Photoelectric conversion element, photoelectric conversion device, mobile body, and building material

[0001] The present invention relates to a photoelectric conversion element, a photoelectric conversion device, a mobile object, and a building material.

[0002] In order to solve the problems of fossil energy depletion and the global environmental problems caused by the use of fossil energy, active research is being conducted on renewable and clean alternative energy sources such as solar energy, wind power, and hydropower. Among these, interest is growing in solar cells that directly convert sunlight into electrical energy. Here, a solar cell refers to a cell that generates current and voltage by utilizing the photovoltaic effect, in which light energy from sunlight is absorbed and electrons and holes are generated.

[0003] Currently, n-p diode-type silicon (Si) single crystal-based solar cells with a light energy conversion efficiency of over 20% are widely known and are actually used for solar power generation. However, these require high-temperature processing steps and the materials themselves are expensive, resulting in high costs per unit of power. Furthermore, there are also supply issues due to the limited silicon resources.

[0004] On the other hand, solar cells using organic materials (hereinafter referred to as "organic solar cells") do not require high-temperature processing and can be produced using a sheet-like substrate in a so-called roll-to-roll manner, which is expected to reduce costs. However, further improvements in power generation efficiency and durability are desired for the practical application of organic solar cells. In particular, perovskite solar cells having crystals with a perovskite structure as a photoelectric conversion layer have excellent photoelectric conversion properties, and therefore development is being advanced toward the practical application of solar cells. For example, Patent Document 1 describes an improvement in conversion efficiency by forming a layer containing a phthalocyanine compound between a hole transport layer (hereinafter also referred to as a "charge transport layer") and perovskite.

[0005] JP 2022-168820 A

[0006] According to the investigations of the present inventors, the above-mentioned conventional techniques require further improvement in conversion efficiency for practical application, and therefore it is necessary to improve the short-circuit current density. An object of the present invention is to provide a photoelectric conversion element with improved short-circuit current density. Another object of the present invention is to provide a photoelectric conversion device, a mobile object, and a building material each having the above-mentioned photoelectric conversion element.

[0007] The above object is achieved by the following invention. Specifically, the present invention provides a photoelectric conversion element having a first electrode, a second electrode, and a photoelectric conversion layer containing a crystal of a perovskite structure and disposed between the first electrode and the second electrode, wherein a charge transport layer containing an amorphous body of a cyclic conjugated compound formed by conjugated bonding of a plurality of pyrrole rings is provided between the photoelectric conversion layer and the first electrode, and wherein an X-ray diffraction spectrum of the charge transport layer using CuKα radiation does not include a diffraction peak having a half-width of 0.5° or less within a Bragg angle 2θ range of 6.5° to 8.5°. The present invention also provides a photoelectric conversion device having the above-described photoelectric conversion element. The present invention also provides a mobile object having the above-described photoelectric conversion element. The present invention also provides a building material having the above-described photoelectric conversion element.

[0008] According to the present invention, it is possible to provide a photoelectric conversion element with improved short-circuit current density.

[0009] Fig. 1 is a schematic cross-sectional view in the thickness direction of an example of a photoelectric conversion element of the present invention. Fig. 2 is a schematic cross-sectional view in the thickness direction of another example of a photoelectric conversion element of the present invention. Fig. 3 is a schematic cross-sectional view in the thickness direction of another example of a photoelectric conversion element of the present invention. Fig. 4 is a perspective view schematically showing an example of a mobile body provided with the photoelectric conversion element of the present invention. Fig. 5 is a perspective view schematically showing an example of a building material provided with the photoelectric conversion element of the present invention.

[0010] One embodiment of the present invention relates to a photoelectric conversion element. The photoelectric conversion element of the present invention is a photoelectric conversion element having a first electrode, a second electrode, and a photoelectric conversion layer containing a crystal of a perovskite structure disposed between the first electrode and the second electrode, wherein a charge transport layer containing an amorphous body of a cyclic conjugated compound formed by conjugated bonding of a plurality of pyrrole rings is disposed between the photoelectric conversion layer and the first electrode, and wherein an X-ray diffraction spectrum of the charge transport layer using CuKα radiation does not contain a diffraction peak having a half-width of 0.5° or less within a Bragg angle 2θ range of 6.5° to 8.5°.

[0011] The present inventors have found that the inclusion of the charge transport layer results in a photoelectric conversion element with excellent short-circuit current density. Although the details of why the present invention provides excellent short-circuit current density are not clear, the mechanism is thought to be as follows.

[0012] According to prior art literature, when a photovoltaic layer contains crystals with a perovskite structure, submicron irregularities occur on the surface. It is believed that filling the recesses of these irregularities with pigment particles made of phthalocyanine compounds, a type of cyclic compound formed by conjugated bonds between multiple pyrrole rings, stabilizes the interfacial bond with the electrode and achieves high photovoltaic conversion efficiency. However, it was found that this alone is insufficient to achieve a higher short-circuit current density.

[0013] Therefore, the present inventors speculate that reducing the crystallinity of a cyclic conjugated compound formed by conjugating a plurality of pyrrole rings, that is, using an amorphous substance, contributes to improving the short-circuit current density.

[0014] Specifically, in the X-ray diffraction spectrum of the charge transport layer using CuKα radiation (λ=1.5418 Å), there is no diffraction peak with a half-width of 0.5° or less within the Bragg angle 2θ range of 6.5° or more and 8.5° or less (either no such diffraction peak exists or a diffraction peak with a half-width greater than 0.5° exists), which enables the short-circuit current density to be improved.

[0015] The absence of a diffraction peak with a half-width of 0.5 or less in the Bragg angle 2θ range of 6.5° to 8.5° indicates that the cyclic conjugated compound is amorphous. The term "amorphous" includes not only those completely free of crystals but also those in which crystalline and amorphous forms are mixed.

[0016] It is believed that amorphous cyclic conjugated compounds generate fewer photoexcitons than those with a higher crystalline content, which reduces hole transport traps and results in improved short-circuit current density. The reason why amorphous compounds generate fewer photoexcitons is thought to be that the molecules of the cyclic conjugated compounds are not aligned, resulting in larger intermolecular distances and less overlap of π conjugation, which means that recombination takes precedence over exciton separation, charge generation, and charge transport.

[0017] The reason why the range in which the Bragg angle 2θ is 6.5° or more and 8.5° or less was focused on is that the intermolecular distance of the cyclic conjugated compound is larger in this scanning range than in the scanning range in which 2θ is larger (assuming from the Bragg formula that the molecular spacing is approximately 10 Å or more and 12 Å or less), and therefore it is assumed that the characteristics of the amorphous body of the cyclic conjugated compound are more clearly exhibited.

[0018] The above-described mechanism makes it possible to achieve the effects of the present invention. The present invention will be described in detail below with reference to preferred embodiments. The present invention is not limited to the following embodiments, and appropriate modifications and improvements to the following embodiments based on the common knowledge of those skilled in the art are also included within the scope of the present invention, provided they do not deviate from the spirit of the present invention. In this specification, the term "layer" does not only refer to a layer having clear boundaries or a flat, thin-film layer, but also to a layer having a concentration gradient in which the contained elements gradually change, or a layer that can form a complex, intricate structure together with other layers.

[0019] 1A is a cross-sectional view schematically illustrating the configuration of one embodiment of the photoelectric conversion element of the present invention. The element has a second electrode 2, an electron transport layer 3, a photoelectric conversion layer 4, a charge transport layer 5, and a first electrode 6 on a substrate 1. One of the first electrode 6 and the second electrode 2 is an anode and the other is a cathode, and current can be extracted by connecting the first electrode 6 and the second electrode 2 to an external circuit.

[0020] The photoelectric conversion layer 4 is excited by light incident through the substrate 1, the second electrode 2, and the electron transport layer 3, or through the first electrode 6 and the charge transport layer 5, and generates electrons or holes. That is, the photoelectric conversion layer 4 generates a current between the first electrode 6 and the second electrode 2. The electron transport layer 3 is a layer disposed between the photoelectric conversion layer 4 and the second electrode 2, or between the second electrode 2 and the first electrode 6, and may not be formed in some cases. A configuration in which a plurality of electron transport layers 3 and photoelectric conversion layers 4 are stacked may be used. Such a configuration may also be called a tandem structure.

[0021] Alternatively, a first electrode 6, a charge transport layer 5, a photoelectric conversion layer 4, an electron transport layer 3, and a second electrode 2 may be arranged on a substrate 1 (FIG. 2).

[0022] Each component will be described below. [Photoelectric Conversion Element] The photoelectric conversion element of the present invention is characterized by having a first electrode 6, a second electrode 2, a photoelectric conversion layer 4 containing a crystal of a perovskite structure and disposed between the first electrode 6 and the second electrode 2, and a charge transport layer 5 between the photoelectric conversion layer 4 and the first electrode 6. In addition, in order to improve photoelectric conversion efficiency, photoelectric conversion elements may be stacked in a tandem configuration. The photoelectric conversion elements to be stacked are not limited to the type of photoelectric conversion element, and may include silicon solar cells, CIGS solar cells, etc., in addition to perovskite solar cells that use a crystal of a perovskite structure for the photoelectric conversion layer 4.

[0023] Methods for forming each layer including the photoelectric conversion layer and the charge transport layer of the present invention include coating methods and vapor deposition methods. Examples of coating methods include dip coating, spin coating, spray coating, inkjet coating, meniscus coating, screen coating, roll coating, die coating, blade coating, curtain coating, and wire bar coating. The coating method involves preparing a coating solution for each layer described below, applying the solution in the desired layer order, and drying the solution. A desired method can be selected from these film formation methods depending on each layer.

[0024] Each layer will be described below. [Substrate] The photoelectric conversion element of the present invention may include a substrate 1, for example, a transparent glass substrate such as soda lime glass or alkali-free glass, a ceramic substrate, or a transparent plastic substrate. In Figures 1A and 1B, when light is taken in from the first electrode 6 side, an opaque material can be used for the substrate 1, and in Figure 2, when light is taken in from the second electrode 2 side, the substrate 1 is made of a transparent material.

[0025] [Electrodes] There are no particular limitations on the materials for the first electrode 6 and the second electrode 2, and conventionally known materials can be used. For example, metals such as gold, silver, titanium, and copper, sodium, sodium-potassium alloy, lithium, magnesium, carbon, carbon nanotubes, aluminum, magnesium-silver mixture, magnesium-indium mixture, aluminum-lithium alloy, and Al / Al ２ O ３ Examples of transparent electrode materials include CuI, ITO (indium tin oxide), and SnO ２ Examples of the conductive transparent material include AZO (aluminum zinc oxide), IZO (indium zinc oxide), GZO (gallium zinc oxide), FTO (fluorine-doped tin oxide), and ATO (antimony-doped tin oxide), as well as conductive transparent polymers. These materials may be used alone or in combination of two or more.

[0026] Of the first electrode 6 and the second electrode 2, at least one electrode on the light incident side is a transparent electrode, and the other may be a transparent electrode or may double as a reflective layer formed of a light-reflective material, or may be a transparent electrode with a reflective layer on the side opposite to the light incident side. As a photoelectric conversion element, it is preferable that the first electrode 6 is a positive electrode. When the first electrode 6 is on the light incident side, the second electrode 2 may be a transparent electrode and the substrate 1 may be a reflective layer. The transparent electrode may be a patterned electrode.

[0027] [Photoelectric Conversion Layer] The photoelectric conversion layer 4 has a crystal with a perovskite structure. The crystal with a perovskite structure used in the present invention is preferably represented by the following general formula [1]: ABX ３[1] In the general formula [1], A is a monovalent cation of an organic molecule or a metal atom, B is a divalent metal cation, and X is a monovalent halide anion. For example, in the case of an organic molecule, A in the general formula [1] is preferably represented by CpNqHr (where p, q, and r are all positive integers). Specific examples include methylammonium and formamidium.

[0028] The metal atom is not particularly limited, but lithium, cesium, sodium, potassium, and rubidium are preferred. These organic molecules or metal atoms may be used alone or in combination of two or more.

[0029] When the constituent cation A is too large to fit within a crystal with a three-dimensional perovskite structure, the resulting crystal is a two-dimensional perovskite structure, a 2.5-dimensional perovskite structure crystal having both two-dimensional and three-dimensional properties, a two-layer crystal of a three-dimensional and two-dimensional perovskite structure, or a crystal with a mixed three-dimensional and two-dimensional perovskite structure, all of which function as the photoelectric conversion layer 4. A two-layer crystal of a three-dimensional and two-dimensional perovskite structure refers to a crystal in which crystals of a three-dimensional and two-dimensional perovskite structure are stacked as independent, separate layers, and a mixed three-dimensional and two-dimensional perovskite refers to a crystal with a structure in which regions or domains of both two-dimensional or 2.5-dimensional layered and three-dimensional perovskite structure crystals are mixed.

[0030] The crystal of the two-dimensional perovskite or 2.5-dimensional perovskite structure is preferably represented by the following general formulas [2] to [4]: ２ A ｎ－１ B ｎ X ３ｎ＋１ [2] R''A ｎ－１ B ｎ X ３ｎ＋１ [3] R''' ２ A ｎ B ｎ X ３ｎ＋１[4] In the above general formulas, general formula [2] forms an RP (Ruddlesden-Popper) type perovskite structure, general formula [3] forms a DJ (Dion-Jacobson) type perovskite structure, and general formula [4] forms an ACI (Alternating cations in the interlayer) type perovskite structure.

[0031] R', R'', and R''' in the above general formulas [2] to [4] are organic molecules or metal cations which may have a substituent, and specific examples thereof include ethylammonium, propylammonium, n-butylammonium, n-hexylammonium, n-octylammonium, 1,6-hexadiammonium, isobutylammonium, 3-(nonafluoro-tert-butyloxy)propylamine, 1,3-propanediammonium, 1,5-pentamethylenediamine, octyldiammonium, 2,2-(ethylenedioxy)bis(ethylammonium), 5-aminovaleric acid, 4-tert-butylammonium, N,N'-dimethylethylene-1,2-diammonium, 2,2,3,3,3-pentafluoropropylammonium, guanidium, propylammonium, propargylamine, alkylammonium, cyclohexylmethylammonium, 4-(aminomethyl)piperidinium, piperidinium, pyrrolidinium, cyclohexylmethylammonium, 4-(aminomethyl)piperidinium, piperidinium, pyrrolidinium, cyclohexylmethylammonium, 4-(aminomethyl)piperidinium, 4-(aminomethyl)pyridin ... ammonium, 4-fluorophenethylammonium, 4-fluorophenethylammonium, trifluoromethylbenzylammonium, pentafluorobenzylammonium, pentafluorophenylethylammonium, 4-methoxyphenethylammonium, imidazolium, pyridinium, 3-thiophenemethylammonium, 2-thiopheneethylammonium, 2-thiopheneformamidium, 2-thiophenemethylammonium, 1-naphthylmethylammonium, 2-naphthylmethylammonium, phenethylammonium, phenylammonium, benzylammonium, 2,5-thiophenedimethylammonium, phenylpropylammonium, 1,4-phenylenedimethanamine, 3-phenyl-2-propene-1-ammonium, phenylbutylammonium, 4-tert-butylbenzylammonium, 3-(aminomethyl)piperidinium, and 4-(aminomethyl)piperidinium are preferred.

[0032] In the general formulas [1] to [4], B represents a metal atom, such as lead, tin, bismuth, zinc, titanium, antimony, nickel, iron, cobalt, silver, copper, gallium, germanium, magnesium, calcium, indium, aluminum, manganese, chromium, molybdenum, and europium. Among these, lead, tin, and bismuth are preferred from the viewpoint of electron orbital overlap. These metal atoms may be used alone or in combination of two or more.

[0033] X in the general formulas [1] to [4] above is a halogen atom or the like, and examples thereof include chlorine, bromine, iodine, sulfur, and selenium. These halogen atoms may be used alone or in combination of two or more. Among these, halogen atoms are preferred because the inclusion of a halogen in the structure makes the perovskite structure crystal more soluble in organic solvents, enabling application to inexpensive printing methods and the like. Furthermore, iodine is more preferred because it narrows the energy band gap of the perovskite structure crystal.

[0034] Specifically, 3D perovskite, 2D perovskite, and mixed 3D / 2D perovskite are MAPbI ３ and FAPbCl ３ , FAPbI ３ , MAPbI ｘ Br ３－ｘ , MAPbI ｘ Cl ３－ｘ , Cs ０．０５ (MA ０．１７ FA ０．８３ ) ０．９５ Pb(I ０．８３ Br ０．１７ ) ３ , Cs ０．０５ FA ０．８８ MA ０．０７ PbI ２．５５ Br ０．４４ , (FAPbI ３ ) ０．９５ (MAPbBr ３ ) ０．０５ , (FAPbI ３ ) ０．８５ (MAPbBr ３ ) ０．１５ , CsPbI ３、CsPbBr ３ 、Cs ｘ (MA) １－ｘ PbI ３ 、Cs ｘ (FA) １－ｘ PbI ３ 、MA ｘ (FA) １－ｘ PbI ３ 、MA ０．１７ FA ０．８３ Pb(I ０．８３ Br ０．１７ ) ３ 、Cs ０．１５ FA ０．８５ PbI ２．５５ Br ０．４５ 、Cs ０．０５ FA ０．８８ MA ０．０７ PbI ２．５６ Br ０．４４ 、Cs ０．１５ FA ０．８５ PbI ２．５５ Br ０．４５ 、(PEA) ２ (MA) ２ Pb ３ I １０ 、(PTA) ２ (MA) ４ Pb ５ I １６ 、(PEA) ２ (MA) ４ Pb ５ I １６ 、(ThMA) ２ (MA) ２ Pb ３ I １０ 、(3BBA) ２ (MA) ２ Pb ３ I １０ 、(ThMA) ２ (FA) ４ Pb ５ I １６ 、(4FPEA) ２ (FA ０．３ MA ０．７ ) ４ Pb ５ I １６ 、(PDMA)FA ２ Pb ３ I １０ 、(3AMPY)(MA)３ Pb ４ I １３ 、(PDMA)MA ５ Pb ６ I １９ 、(PDMA)MA ３ Pb ４ I １３ 、(TTDMA)MA ３ Pb ４ I １３ 、(TTDMA)MA ４ Pb ５ I １６ 、 (BA ０．９ PEA ０．１ ) ２ MA ４ Pb ５ I １６ 、 (BA ０．９ PEA ０．１ ) ２ MA ３ Pb ４ I １３ 、(4FFEA) ２ MA ３ Pb ４ I １３ 、(4FFEA) ２ MA ４ Pb ５ I １６ (BA) ２ MA ２ Pb ３ I １０ 、(BA) ２ MA ３ Pb ４ I １３ 、(TEA) ２ MA ２ Pb ３ I １０ 、(BA) ２ MA ４ Pb ５ I １６ 、(BA) ２ MA ３ Pb ４ I １３ 、Cs.Br ３ 、CsSﾎI ３ 、FA ０．７５ MA ０．２５ Se ０．９５ Ge ０．０５ I ３ 、FAMASGGeI３ , FASnBr ３ , FASnI ３ , M.A. ２ Sn ３ I ８ , MASnBr ３ , MASnGeI ３ , MASnI ３ is preferred.

[0035] Depending on the purpose, the A site, B site, or X site in the above general formula may be adjusted to be insufficient or excessive, and the combination of x1 to x5 may be changed depending on the purpose. Combinations of x1 to x5 are, for example, as shown in Table 1. Particularly preferred ranges are 0.03≦x1≦0.10, 0.80≦x2≦0.96, 0.95≦x3≦1.05, 0.80≦x4≦0.96, and 2.95≦x5≦3.05. MACl may also be included as a material for forming perovskite crystals.

[0036]

[0037] In the above specific examples, "MA" represents methylammonium, "FA" represents formamidinium, "PEA" represents phenethylammonium, "PTA" represents phenyltriethylammonium, "ThMA" represents 2-thiophenemethylammonium, "3BBA" represents 3-bromobenzylammonium, "3AMPY" represents 3-(aminomethyl)pyridine, "PDMA" represents 1,4-phenylenedimethaneammonium, "TTDMA" represents thieno[3,2-b]thiophene-2,5-diyldimethaneammonium, "4FPEA" represents 4-fluorine phenethylammonium, "BA" represents butylammonium, and "TEA" represents 2-thiophenethylammonium.

[0038] The perovskite crystal preferably has a cubic structure in which a metal atom B is located at the body center, an organic molecule A at each vertex, and a halogen atom X at the face center. Although the details are not clear, it is presumed that such a structure allows the orientation of the octahedra in the crystal lattice to be easily changed, thereby increasing the mobility of electrons in the perovskite crystal and improving the photoelectric conversion efficiency of the photoelectric conversion element.

[0039] The perovskite crystal used in the present invention is preferably a crystalline semiconductor. A crystalline semiconductor refers to a semiconductor in which a scattering peak can be detected by measuring an X-ray scattering intensity distribution. When the perovskite crystal is a crystalline semiconductor, the mobility of electrons in the perovskite crystal increases, improving the photoelectric conversion efficiency of the photoelectric conversion element.

[0040] The thickness of the photoelectric conversion layer 4 according to the present invention is preferably 5 nm or more and 2000 nm or less. A thickness of 5 nm or more allows sufficient absorption of light, and a thickness of 2000 nm or less allows generated charges to be transported to each electrode. A more preferred lower limit is 50 nm or more, a more preferred upper limit is 1200 nm, an even more preferred lower limit is 100 nm, and an even more preferred upper limit is 1000 nm.

[0041] [Charge Transport Layer] The photoelectric conversion element of the present invention has a charge transport layer 5 between the photoelectric conversion layer 4 and the first electrode 6, which contains an amorphous body of a cyclic conjugated compound formed by conjugating a plurality of pyrrole rings. The cyclic conjugated compound formed by conjugating a plurality of pyrrole rings used in the present invention is preferably a porphyrin compound or a phthalocyanine compound, more preferably a phthalocyanine compound, from the viewpoint of the extent of the π-electron cloud that serves as the starting point for interactions. In the photoelectric conversion element of the present invention, the phthalocyanine compound preferably has no central metal or the central metal is gallium, aluminum, titanium, or silicon, more preferably a gallium phthalocyanine compound. The phthalocyanine compound may have no central element or may have a central metal. Examples of the central element include Ga, Cu, Ti, Al, Si, Zn, V, Pb, Pt, Co, Sn, Mg, Fe, and Mn. Among these, a gallium phthalocyanine compound having Ga as the central element is preferred.

[0042] Specific examples of the cyclic conjugated compound of the present invention in which a plurality of pyrrole rings are conjugated are listed below. Specific examples of the cyclic conjugated compound of the present invention in which a plurality of pyrrole rings are conjugated include porphyrin derivatives such as tetraphenylporphyrin, diphenylporphyrin, tetrapyridylporphyrin, copper porphyrin, copper tetraphenylporphyrin, copper octaethylporphyrin, cobalt tetraphenylporphyrin, octaethylporphyrin, chlorophenylporphyrin, methoxyphenylporphyrin, methylphenylporphyrin, zinc porphyrin, magnesium porphyrin, octabutoxyporphyrin, manganese chloroporphyrin, metal-free tetraazaporphyrin, copper tetraazaporphyrin, zinc tetraazaporphyrin, nickel tetraazaporphyrin, titanyltetraazaporphyrin, tetraphenyltetraazaporphyrin, and octaphenyltetraazaporphyrin.

[0043] Specific examples of the cyclic conjugated compound in which a plurality of pyrrole rings are conjugated in the present invention include phthalocyanine derivatives such as hydroxygallium phthalocyanine, chlorogallium phthalocyanine, copper phthalocyanine, zinc phthalocyanine, phthalocyanine, cobalt phthalocyanine, titanyl phthalocyanine, dichlorotin phthalocyanine, magnesium phthalocyanine, tin phthalocyanine, lead phthalocyanine, iron phthalocyanine, vanadyl phthalocyanine, chloroaluminum phthalocyanine, nickel phthalocyanine, dichlorosilicon phthalocyanine, indium chlorophthalocyanine, manganese phthalocyanine, chloroiron phthalocyanine, and platinum phthalocyanine. In the photoelectric conversion element of the present invention, the gallium phthalocyanine compound is preferably hydroxygallium phthalocyanine.

[0044] Specific examples of the cyclic conjugated compound in the present invention in which a plurality of pyrrole rings are conjugated include naphthalocyanine derivatives such as naphthalocyanine, magnesium naphthalocyanine, copper naphthalocyanine, magnesium naphthalocyanine, cobalt naphthalocyanine, vanadyl naphthalocyanine, tin naphthalocyanine, and dichlorotin naphthalocyanine. In the present invention, the chemical structure of the cyclic conjugated compound in which a plurality of pyrrole rings are conjugated can be confirmed by, for example, nuclear magnetic resonance (NMR) spectroscopy.

[0045] In the photoelectric conversion element of the present invention, it is preferable that the charge transport layer 5 contains a resin. From the viewpoint of film formability and charge transport ability, the content of the resin in the charge transport layer 5 is preferably 3 parts by mass or more and 30 parts by mass or less, and more preferably 5 parts by mass or more and 20 parts by mass or less, when the content of the cyclic conjugated compound in the charge transport layer 5 is taken as 100 parts by mass. The content of the resin can be quantified using a nuclear magnetic resonance (NMR) apparatus or a gas chromatography apparatus.

[0046] The molecular weight of the resin is preferably 10,000 or more. Furthermore, the Tg (glass transition temperature) of the resin is preferably 95°C or less. Within this range, the resin is more likely to come into close contact with the charge transport material (charge transport particles), allowing for the formation of a more effective charge distribution. The glass transition temperature can be determined by a differential scanning calorimeter (DSC).

[0047] Resins that can be preferably used in the present invention include polyester resins, polycarbonate resins, polyvinyl acetal resins, polyvinyl butyral resins, acrylic resins, polyvinyl alcohol resins, cellulose resins, polystyrene resins, polyvinyl acetate resins, and polyvinyl chloride resins.

[0048] The charge transport layer may contain an aromatic ring compound containing a hydroxyl group, and from the viewpoint of film-forming properties and charge transport ability, the content of the aromatic ring compound containing a hydroxyl group in the charge transport layer is preferably 1% by mass or more and 30% by mass or less, and more preferably 5% by mass or more and 20% by mass or less, relative to the content of the cyclic conjugated compound formed by covalently bonding multiple pyrrole rings. Examples of aromatic ring compounds containing a hydroxyl group that are preferably used in the present invention include calixarene compounds.

[0049] In the photoelectric conversion element of the present invention, in the X-ray diffraction spectrum of the charge transport layer 5 using CuKα radiation, there is no diffraction peak with a half-width of 0.5° or less within the Bragg angle 2θ range of 6.5° to 8.5°. That is, in the X-ray diffraction spectrum of the charge transport layer using CuKα radiation, there may be a diffraction peak with a half-width of 0.6° or more, preferably a peak with a half-width of 1.0° or more, within the Bragg angle 2θ range of 6.5° to 8.5°. This means that the cyclic conjugated compound formed by conjugating multiple pyrrole rings is amorphous. Furthermore, the amorphous substance may have an extremely small crystalline content, resulting in a peak that is too broad to be detected.

[0050] In the photoelectric conversion element of the present invention, the charge transport layer preferably has a peak in the Bragg angle 2θ range of 6.8° to 7.1° and 16.4° to 16.8° in an X-ray diffraction spectrum using CuKα radiation, which improves the short-circuit current density of the photoelectric conversion element.

[0051] Examples of a dispersion method for forming particles from an amorphous cyclic conjugated compound formed by conjugating a plurality of pyrrole rings include methods using a paint shaker, a sand mill, a ball mill, and a liquid collision type high-speed disperser.

[0052] Among these, sand mills granulate amorphous materials using shear forces from the rotation of a rotating disk inside the mill and the grinding media, such as glass beads, but the half-width of the peak changes as the crystallinity changes depending on the dispersion conditions, such as the dispersion time, amount of beads, and disk rotation speed. For example, if the rotation speed is reduced to a level that does not cause uneven dispersion, the half-width tends to increase.

[0053] The X-ray diffraction spectrum of the charge transport layer 5 used in the present invention and the presence of cyclic compounds formed by conjugated bonds between multiple pyrrole rings were measured by removing the layers above the charge transport layer 5 of the photoelectric conversion element of the present invention with an organic solvent such as chloroform, exposing the surface of the charge transport layer 5, and then performing the following method.

[0054] [Analysis of Compound Amount] The surface of the charge transport layer 5 was wiped with a cotton swab or the like soaked in a solvent, dissolved in heavy water sulfuric acid, and subjected to 1H-NMR measurement (apparatus: AVANCE3-500, manufactured by BRUKER). The wiped components were subjected to mass and structural analysis using GPC, MALDI-TOF-MS, IR, and gas chromatography to confirm the presence of the compound. The film thickness was confirmed by cutting the photoelectric conversion element, fixing it to an inclined sample stage, and then using a cross-sectional SEM (apparatus: SmartSEM, manufactured by Carl Zeiss K.K.).

[0055] MALDI-TOF-MS analysis was performed under the following conditions, and the molecular weight was confirmed from the peak top value obtained. Measuring instrument used: Matrix-assisted laser desorption ionization time-of-flight mass spectrometer (MALDI-TOF MS) Ultraflex, manufactured by Bruker Daltonics, Acceleration voltage: 20 kV Mode: Reflector Molecular weight standard: Fullerene C60

[0056] [X-ray Diffraction Measurement] The X-ray diffraction spectrum of the exposed charge transport layer 5 was measured, and the 2θ value of the peak present in the Bragg angle 2θ range of 6.5° to 8.5° (referred to as a peak present in the 2θ range of 6.5° to 8.5° in Table 2) and the half-value width of the peak (referred to as half-value width in Table 2) were determined. Measuring equipment used: X-ray diffraction apparatus RINT-TTRII, manufactured by Rigaku Electric Co., Ltd. X-ray tube: Cu X-ray wavelength: Kα1 Tube voltage: 50 KV Tube current: 300 mA Scan method: 2θ-θ scan Scan speed: 4.0° / min Sampling interval: 0.02° Start angle 2θ: 3.0° Stop angle 2θ: 30.0° Goniometer: Rotor horizontal goniometer (TTR-2) Filter: None Detector: Scintillation counter Incident monochromator: Used Slit: Variable slit (parallel beam method) Counter monochromator: Not used Divergence slit: Open Divergence vertical limiting slit: 10.00 mm Scattering slit: Open Receiving slit: Open

[0057] [Second Charge Transport Layer] From the viewpoint of film compatibility of the charge transport layer, the photoelectric conversion element of the present invention preferably has a second charge transport layer 7 between the charge transport layer 5 and the first electrode 6, as shown in Fig. 1B . When the photoelectric conversion element has the second charge transport layer 7, the charge transport layer containing phthalocyanine crystals (charge transport layer 5) becomes the first charge transport layer.

[0058] The material for the second charge transport layer 7 is not particularly limited, and examples thereof include spirofluorene compounds, triphenylamine compounds, chrysene compounds, pyrene compounds, phthalocyanine compounds, carbazole compounds, fluorene compounds, phenylcyclohexane compounds, benzidine compounds, phenoxazine compounds, phenylenediamine compounds, thiocyanate compounds, and thiophene compounds. In particular, from the viewpoint of compatibility at the film interface, those having an aromatic ring are preferred, and Spiro-OMeTA, PTAA, and phthalocyanine compounds are preferred.

[0059] The second charge transport layer may contain a dopant as an additive to improve its charge transport capability. Examples of a substance that can be used as a dopant include lithium compounds such as bis(trifluoromethanesulfonyl)imide lithium, cobalt compounds such as [tris(2-(1H-pyrazol-1-yl)-4-tert-butylpyridine)cobalt(3)tris(bis(trifluoromethylsulfonyl)imide)], boron compounds such as tetrakis(pentafluorophenyl)borate, molybdenum compounds such as tris[1-(methoxycarbonyl)-2-(trifluoromethyl)-ethane-1,2-dithiolene]molybdenum, organic compounds having a tetracyanoquinodimethane skeleton such as 2,3,4,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane, and organic compounds having a pyridine skeleton such as 4-tert-butylpyridine.

[0060] 1A , an electron transport layer 3 may be disposed between the second electrode 2 and the photoelectric conversion layer 4. The material for the electron transport layer 3 is not particularly limited, and examples thereof include N-type conductive polymers, N-type low-molecular-weight organic semiconductors, N-type metal oxides, N-type metal sulfides, alkali metal halides, alkali metals, and surfactants. Specific examples thereof include cyano group-containing polyphenylene vinylene, boron-containing polymers, bathocuproine, bathophenanthrene, hydroxyquinolinatoaluminum, oxadiazole compounds, benzimidazole compounds, naphthalene tetracarboxylic acid compounds, fullerene compounds, perylene derivatives, phosphine oxide compounds, phosphine sulfide compounds, fluoro group-containing phthalocyanines, titanium oxide, zinc oxide, indium oxide, tin oxide, gallium oxide, tin sulfide, indium sulfide, and zinc sulfide.

[0061] The thickness of the electron transport layer 3 is preferably 1 nm or more in lower limit and 2000 nm or more in upper limit. If the thickness of the electron transport layer 3 is 1 nm or more, holes can be sufficiently blocked, and if the thickness is 2000 nm or less, the electron transport layer is less likely to act as a resistance during electron transport, resulting in high photoelectric conversion efficiency. The thickness is more preferably 3 nm or less in lower limit and 1000 nm or more in upper limit, and even more preferably 5 nm or less in lower limit and 500 nm or more in upper limit.

[0062] <Application Examples> Application examples of the present invention relate to photoelectric conversion devices, mobile objects, and building materials. [Photoelectric Conversion Device] The photoelectric conversion device of the present invention includes the photoelectric conversion element of the present invention. A photoelectric conversion device can be constructed by using multiple photoelectric conversion elements of the present invention. When multiple photoelectric conversion elements are connected, such a photoelectric conversion device can also be called a photoelectric conversion cell or a photoelectric conversion module. The photoelectric conversion element may be stacked with elements having different absorption wavelengths to increase the output voltage. The photoelectric conversion device may also include the photoelectric conversion element of the present invention and an inverter. The inverter may be a converter that converts direct current to alternating current. The photoelectric conversion device may include a power storage unit connected to the photoelectric conversion element. The power storage unit is not limited as long as it can store electricity. Examples include secondary batteries using lithium ions, all-solid-state batteries, and electric double-layer capacitors. To impart functionality such as maintaining or increasing the amount of incident light, a surface layer that is resistant to water and dirt, or a function for collecting or guiding light may be added.

[0063] [Mobile Object] The mobile object of the present invention includes the photoelectric conversion element of the present invention. FIG. 3 is a perspective view schematically illustrating one embodiment of a mobile object including the photoelectric conversion element of the present invention. The mobile object 30 includes the photoelectric conversion element 31 of the present invention and a vehicle 32 including the photoelectric conversion element 31. The photoelectric conversion element 31 is disposed in a position on the vehicle 32 where it can receive external light. If the mobile object 30 is an automobile, it may be disposed on the roof. The electrical energy obtained by the photoelectric conversion element 31 may power the mobile object 30 or other electrical equipment. Electrical energy generated by the power of the mobile object 30 may be used to power the photoelectric conversion element 31. If the mobile object 30 is an automobile, frictional energy generated by braking may be converted into electrical energy and used to control the photoelectric conversion element 31. The mobile object 30 may be, for example, an automobile, a motorcycle, a railroad vehicle, a ship, or an aerial vehicle including an artificial satellite, an airplane, or a drone. The configuration of the vehicle 32 of the mobile object 30 is not particularly limited, but it is preferably made of a high-strength material.

[0064] [Building Material] The building material of the present invention has the photoelectric conversion element of the present invention. Fig. 4 is a perspective view schematically showing one embodiment of a building material including the photoelectric conversion element of the present invention. The building material 40 may be the roof of a building. The building material 40 of this embodiment has the photoelectric conversion element 41 of the present invention, a protective member 42 that protects the photoelectric conversion element 41, a heat dissipation member 43, and exterior coverings 44a and 44b.

[0065] The building material 40 of the present invention may have a heat dissipation member 43 having a higher thermal conductivity than the photoelectric conversion element 41. When used on a roof or the like, sunlight may increase the temperature of the photoelectric conversion element 41, potentially reducing the photoelectric conversion efficiency. The use of the heat dissipation member 43 can reduce the reduction in photoelectric conversion efficiency. Examples of the heat dissipation member 43 include a metal, an alloy, a liquid metal, and a liquid resin.

[0066] Furthermore, the building material 40 of the present invention may have exterior coatings 44a and 44b. The exterior coatings 44a and 44b may emit different colors or may be the same. The exterior coatings 44a and 44b may be made of the same material or different materials. Paint or a transparent substrate may be used as the exterior coating. Materials with low light absorption and high heat insulation properties are preferred.

[0067] In addition to the above application examples, the following application examples can be mentioned: Portable devices include, for example, calculators, sensors, and small solar panels; Wearable devices include, for example, eyeglass-type terminals, wristwatch-type terminals, and portable medical equipment; Sheet structures supported by multiple frames include, for example, tents, greenhouses, and truck beds; Fixed structures include, for example, road panels, floating panels, building materials that take advantage of the flexibility of the substrate, wall-type building materials, glass-type building materials, and mega solar panels.

[0068] [Method for manufacturing photoelectric conversion element] The method for manufacturing the photoelectric conversion element of the present invention includes the steps of forming a first electrode, forming a second electrode, and forming a photoelectric conversion layer containing crystals with a perovskite structure between the first electrode and the second electrode. Each step of the manufacturing method will be described below.

[0069] (Step of forming a first electrode and step of forming a second electrode) The method for manufacturing a photoelectric conversion element of the present invention includes a step of forming a first electrode and a step of forming a second electrode. For the step of forming the first electrode and the step of forming the second electrode, an appropriate method can be selected depending on the material of the first electrode and the material of the second electrode, respectively. Examples of such methods include, but are not limited to, sputtering vacuum deposition, CVD (chemical vapor deposition), and SPD (spray pyrolysis deposition). The materials of the first electrode and the second electrode are as described above. When either or both of the first electrode and the second electrode are transparent electrodes, the thickness of the transparent electrode is preferably 0.03 μm or more and 3 μm or less. When manufacturing a solar cell, cutting may be performed between each step to form a circuit. Examples of cutting include mechanical patterning and laser patterning.

[0070] (Modularization Process) The elements having electrodes formed thereon may be sealed. Examples of sealing methods include sealing with a resin or sealing with a film. Examples of materials used for sealing include silazane, silicone rubber, resins having a siloxane skeleton, and glass. In addition, from the viewpoint of suppressing adhesion between elements that occurs when winding in a roll-to-roll manner, the surfaces of the sealed elements may be subjected to a hairline treatment.

[0071] (Step of forming photoelectric conversion layer) The step of forming the photoelectric conversion layer may include a step of applying a liquid containing the material for the photoelectric conversion layer described above. Examples of application methods include spin coating, blade coating, slit die coating, screen printing, bar coating, casting, print transfer, immersion and lifting, inkjet printing, spraying, and vacuum deposition. Among these, an appropriate method is selected depending on the properties of the photoelectric conversion layer to be produced, such as thickness control and orientation control.

[0072] In order to remove the solvent or dispersion medium from the liquid containing the material of the applied photoelectric conversion layer, annealing may be performed under reduced pressure or in an inert atmosphere (nitrogen or argon atmosphere). The temperature of the annealing is preferably 40° C. or higher and 300° C. or lower, more preferably 50° C. or higher and 150° C. or lower. Note that annealing is preferable because it may increase the contact area at the interface between the stacked layers due to the penetration of the materials constituting each layer into each other, thereby increasing the short-circuit current.

[0073] (Step of Forming Charge Transport Layer) The step of forming the charge transport layer is preferably a method of applying a liquid containing the material for the charge transport layer described above. Examples of the application method include spin coating, blade coating, slit die coating, screen printing, bar coating, casting, print transfer, immersion and lifting, ink jet printing, spraying, and vacuum deposition.

[0074] Examples of the step of forming the charge transport layer include a method of disposing charge transport particles on the surface of the photoelectric conversion layer, then applying a resin solution in which a resin is dissolved, and then drying the resulting solution; a method of applying a resin solution in which a resin is dissolved, on the surface of the photoelectric conversion layer, then disposing charge transport particles, and then drying the resin solution; and a method of applying a solution in which charge transport particles are dispersed in a resin solution in which a resin is dissolved, on the surface of the photoelectric conversion layer, and then drying the resulting solution.

[0075] The present invention will be described in more detail below using examples and comparative examples. The present invention is not limited to the following examples without departing from the gist of the present invention. In the following description of the examples, "parts" are by mass unless otherwise specified.

[0076] (Preparation Process of Particles 1 Containing Amorphous Cyclic Compound Formed by Conjugated Bonds of Multiple Pyrrole Rings) Step (1) Under a nitrogen flow atmosphere, 5.46 parts of orthophthalonitrile and 45 parts of α-chloronaphthalene were charged into a reaction vessel, and the mixture was heated to 30°C and maintained at this temperature. Next, 3.75 parts of gallium trichloride were charged at this temperature (30°C). The water concentration of the mixed solution at the time of charging was 150 ppm. The mixture was then heated to 200°C. Next, under a nitrogen flow atmosphere, the mixture was reacted at 200°C for 4.5 hours, cooled, and when the temperature reached 150°C, the product was filtered. The resulting filtrate was dispersed and washed using N,N-dimethylformamide at 140°C for 2 hours, followed by filtration. The resulting filtrate was washed with methanol and dried, yielding chlorogallium phthalocyanine particles in a yield of 71% by mass.

[0077] Step (2): 4.65 parts of the chlorogallium phthalocyanine particles were dissolved in 139.5 parts of concentrated sulfuric acid at 10°C, and the solution was added dropwise to 620 parts of ice water under stirring to reprecipitate the mixture, which was then filtered under reduced pressure using a filter press. A No. 5C filter (manufactured by Advantec Co., Ltd.) was used. The resulting wet cake (filtrate) was dispersed and washed with 2% aqueous ammonia for 30 minutes, and then filtered using a filter press. The resulting wet cake (filtrate) was then dispersed and washed with ion-exchanged water, and then filtered three times using a filter press. Finally, freeze-drying was performed to obtain hydroxygallium phthalocyanine particles (hydrated hydroxygallium phthalocyanine particles) with a solids content of 23% by mass in a yield of 71% by mass. The hydroxygallium phthalocyanine particles were dried using a Hyper Dry dryer (trade name: HD-06R, frequency (oscillation frequency): 2455 MHz ± 15 MHz, manufactured by Nippon Biocon Co., Ltd.) to obtain particles 1 with a moisture content of 1.0% by mass or less. It was confirmed that particle 1 had peaks in the range of Bragg angle 2θ of 6.8° to 7.1° and 16.4° to 16.8° in the X-ray diffraction spectrum using CuKα radiation.

[0078] (Preparation of Resin Solution 1) 1.0 g of polyvinyl butyral (product name: BM-2, manufactured by Sekisui Chemical Co., Ltd.) was dissolved in 19 g of 2-propanol with stirring for 24 hours to obtain Resin Solution 1.

[0079] (Preparation of Resin Solution 2) Resin solution 2 was obtained by dissolving 1.0 g of polyacrylic acid (molecular weight 5000, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) in 19 g of ethanol with stirring for 24 hours.

[0080] Example 1 Formation of Electron Transport Layer A glass substrate with ITO was cleaned, and tin (II) oxide adjusted to a concentration of 3% by mass was applied thereon by spin coating. The substrate was then heated at 150°C for 30 minutes to form a thin-film electron transport layer having a thickness of 15 nm.

[0081] [Formation of Photoelectric Conversion Layer] 22.4 mg of methylammonium bromide, 172 mg of formamidium iodide, and 576 mg of lead iodide were dissolved in 600 μL of N,N-dimethylformamide and 160 μL of dimethyl sulfoxide, and the mixture was stirred for 1 hour (Solution 1). Furthermore, 389.72 mg of cesium iodide was dissolved in 1000 μL of dimethyl sulfoxide, and the mixture was stirred for 1 hour (Solution 2). Then, 40 μL of the dissolved cesium iodide solution (Solution 2) was added to Solution 1 to prepare a photoelectric conversion layer coating solution. This coating solution was spin-coated on the electron transport layer, resulting in the formation of a Cs ０．０５ (FA ０．８３ MA ０．１７ ) ０．９６ Pb(I ０．９５ Br ０．０５ ) ３ A photoelectric conversion layer having a thickness of 500 nm was formed.

[0082] [Formation of Charge Transport Layer 1] To prepare a coating liquid for a charge transport layer, 5.0 g of the particles 1 and 0.5 g of a calixarene compound (exemplified compound 1 described in JP 2003-207913 A) were sealed together with 560 g of 2-propanol and 580 g of zirconia beads, and the mixture was dispersed for 30 hours using a sand mill (manufactured by Igarashi Machine Manufacturing (now Imex), disk diameter 70 mm, number of disks: 5) by rotating the disks at 300 rpm to prepare a coating liquid for a charge transport layer. The coating liquid for a charge transport layer was spin-coated on the photoelectric conversion layer to form a charge transport layer with a thickness of 100 nm.

[0083] [Introduction of Second Charge Transport Layer] 1.5 g of Spiro-OMeTAD, a material for the second charge transport layer, was dissolved in 2.2 g of chlorobenzene. 36 μL of an acetonitrile solution obtained by dissolving 0.2 g of lithium-bis(trifluoromethanesulfonyl)imide in 0.3 g of acetonitrile was added to this chlorobenzene solution, and 36 μL of t-butylpyridine (TBP) were added and mixed. 58 μL of an acetonitrile solution obtained by dissolving 0.11 g of [tris(2-(1H-pyrazol-1-yl)-4-tert-butylpyridine)cobalt(III) tris(bis(trifluoromethylsulfonyl)imide)] in 0.3 g of acetonitrile was added to prepare a second charge transport coating solution. This solution was applied to the charge transport layer by spin coating to form a second charge transport layer with a thickness of 80 nm.

[0084] [Formation of First Electrode] A first electrode having a thickness of 80 nm and an area of ​​0.09 cm2 was formed on the second charge transport layer. ２ A gold electrode was formed by vacuum deposition to obtain a photoelectric conversion element.

[0085] [Evaluation of Short-Circuit Current Density] A power supply (manufactured by Keithley, Model 236) was connected between the electrodes of the photoelectric conversion element, and an intensity of 100 mW / cm ２ The device was irradiated with a constant amount of light using a solar simulator (manufactured by Yamashita Denso Co., Ltd.) and the generated current density was measured. The results are shown in Table 2.

[0086] (Comparative Example 1) A photoelectric conversion element was prepared and evaluated in the same manner as in Example 1, except that the cyclic conjugated compound was changed to one shown in Table 2 (particle 1 used in Example 1 of JP-A No. 2022-168820). The results are shown in Table 2.

[0087] (Examples 2 to 14, Comparative Example 2) Photoelectric conversion elements are prepared in the same manner as in Example 1, except that the type of cyclic conjugated compound, whether or not a resin solution is added when preparing the charge transport layer solution, the type and amount of resin solution, and whether or not a second charge transport layer is formed are changed. The results are shown in Table 2. A cyclic conjugated compound is prepared by using an arbitrary cyclic conjugated compound in a sand mill in the same manner as in Example 1, and adjusting the dispersion conditions (rotation speed, etc.) so that the half-width of the peak has the ratio shown in Table 2.

[0088] The resin ratios in Table 2 are the resin contents (parts by mass) in the charge transport layer when the content of the cyclic conjugated compound in the charge transport layer is taken as 100 parts by mass.

[0089]

[0090] The present invention is not limited to the above-described embodiments, and various modifications and variations can be made without departing from the spirit and scope of the present invention. Therefore, the following claims are appended to apprise the public of the scope of the present invention.

[0091] This application is related to Japanese Patent Application No. 2023-184761 filed on October 27, 2023, Japanese Patent Application No. 2023-184756 filed on October 27, 2023, Japanese Patent Application No. 2023-184750 filed on October 27, 2023, Japanese Patent Application No. 2023-216294 filed on December 21, 2023, Japanese Patent Application No. 2023-216296 filed on December 21, 2023, and Japanese Patent Application No. 216299, Japanese Patent Application No. 2024-022244 filed on February 16, 2024, Japanese Patent Application No. 2024-022251 filed on February 16, 2024, Japanese Patent Application No. 2024-022246 filed on February 16, 2024, Japanese Patent Application No. 2024-086011 filed on May 28, 2024, and Japanese Patent Application No. 2024-186513 filed on October 23, 2024. Priority is claimed based on the above, and all of the contents thereof are incorporated herein by reference.

[0092] REFERENCE SIGNS LIST 1 substrate 2 second electrode 3 electron transport layer 4 photoelectric conversion layer 5 charge transport layer 6 first electrode 7 second charge transport layer 30 mobile body 31, 41 photoelectric conversion element 32 body 40 building material 42 protective member 43 heat dissipation member 44a, 44b exterior

Claims

1. A photoelectric conversion element having a first electrode, a second electrode, and a photoelectric conversion layer containing a crystal of a perovskite structure disposed between the first electrode and the second electrode, wherein a charge transport layer containing an amorphous body of a cyclic conjugated compound formed by conjugating a plurality of pyrrole rings is disposed between the photoelectric conversion layer and the first electrode, and wherein an X-ray diffraction spectrum of the charge transport layer using CuKα radiation has no diffraction peak with a half-width of 0.5° or less within the range of a Bragg angle 2θ of 6.5° or more and 8.5° or less.

2. The photoelectric conversion element according to claim 1, wherein in an X-ray diffraction spectrum using CuKα radiation for the charge transport layer, a diffraction peak having a half-width of 0.6° or more is present within a range of a Bragg angle 2θ of 6.5° or more and 8.5° or less.

3. The photoelectric conversion element according to claim 1, further comprising a second charge transport layer between the first electrode and the charge transport layer.

4. The photoelectric conversion element according to any one of claims 1 to 3, wherein the charge transport layer contains a resin.

5. The photoelectric conversion element according to claim 4, wherein the content of the resin in the charge transport layer is 3 parts by mass or more and 30 parts by mass or less when the content of the cyclic conjugated compound in the charge transport layer is 100 parts by mass.

6. The photoelectric conversion element according to any one of claims 1 to 5, wherein the cyclic conjugated compound is a phthalocyanine compound.

7. The photoelectric conversion element according to claim 6, wherein the phthalocyanine compound has no central metal or the central metal is gallium, aluminum, titanium or silicon.

8. The photoelectric conversion element according to claim 6 or 7, wherein the phthalocyanine compound is a gallium phthalocyanine compound.

9. The photoelectric conversion element according to claim 8, wherein the gallium phthalocyanine compound is hydroxygallium phthalocyanine.

10. The photoelectric conversion element according to any one of claims 1 to 9, wherein the charge transport layer has a peak in an X-ray diffraction spectrum using CuKα radiation, where the Bragg angle 2θ is in the range of 6.8° or more and 7.1° or less, and 16.4° or more and 16.8° or less.

11. A photoelectric conversion device comprising the photoelectric conversion element according to any one of claims 1 to 10.

12. A moving object having a photoelectric conversion element according to any one of claims 1 to 10.

13. A building material comprising the photoelectric conversion element according to any one of claims 1 to 10.

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